Oil analysis /what they says/

The report is not showing fuel in oil, and wear metals are very good, so seems more probable that the oil is shearing viscosity. I found this to be a similar situation with my Detroit 12.7 pre-egr. I was using Delo in it, and got shearing and losing viscosity, with no fuel showing up in the report. That was for the first 100,000 miles on the factory rebuilt engine doing 15K oil changes. After that, I switched to Schaeffer 15w40 syn blend and the viscosity has held up just fine, even at 25K oil changes I am doing now.

I have come to believe that different engines just plain prefer different oils. Rotella is a good oil, but your engine doesn't seem to like it, and wants to brutalize it to death. Change to another brand, like Delvac, and give it a try. See what a sample on that says. I got lucky on my first switch, that the Schaeffer I am using now, the engine seems to really have taken a liking to it. You might experience the same thing by going to Delvac. If not, then try another brand. If after several different brands, you have some issue going on. Without fuel dilution actually showing up in the sample, it is hard to tell.

25% of any gallon of oil is additive package. The viscosity improvers that provide the ability to operate as a 15w40 are part of the add pack. The base oil usually doesn't shear, it is the VI in the add pack. And not every oil out there uses the same add pack in their oil. All oils may be a CJ-4, but that is about as far as it goes. Each has their own "witches brew" that is part of the oil.

 

I would not worry just yet, even though the viscosity is a little low, the copper and iron are a little bit higher than I would like but that is ok too. You said its you're 1st oil change, I'm guessing it sat for at least 2-3 weeks before you bought it allowing a mild hazing of rust on the cylinder walls, 1st oil change/analysis after 6 weeks off for surgery about gave me a heart attack. I would run it 10 or 12,000 more and change/check it again before I panicked. I know we aren't supposed to bad mouth anybody on here, so I will just add that when ever there was a blue and yellow oval on the top right of my oil analysis I made sure I witnessed for myself the cleaning of the machine BEFORE my test, I'm just sayin'...

 

Try a different oil and change it again in 10,000 miles. Everything but the viscosity looks great, so I wouldn't be worried but for the choice of oil.

 

Are you sure 15w40 was put in there? Absolutely sure?

Here's the other problem: It's speedco

 

I just went to Speedco for the first time for my 990,000 mile oil change, and nothing you guys are saying really surprises me. What kind of PM comes without a brake inspection?

 

I was talking to owner op couple days ago and he said he was running synthetic on his truck and oil change interval is 70K for him. He says he gets oil analysis done and supposedly it's good for that amount of miles.

 

Or coolant. It's possible, but you have to be sure conditions are the same and the truck is level both times.